Resonant X-ray diffraction study of chiral polar skyrmions in PbTiO3/SrTiO3 superlattices

ORAL

Abstract

Emergent topologies in ferroelectric heterostructures—the polar analogs of magnetic vortices and skyrmions—have become a recent topic of interest for their potential to host exotic functionalities (e.g., emergent chirality and negative capacitance). These topologies can be stabilized in low-dimensional ferroelectrics; namely, superlattices of PbTiO3/SrTiO3. Polar skyrmion structures have been observed in PbTiO3/SrTiO3 superlattices grown on SrTiO3 substrates with a combination of scanning transmission electron microscopy, X-ray diffraction, and second-principles calculations. Using resonant soft X-ray diffraction, we study the chirality of these polar skyrmions and show that the skyrmions have a preferred handedness. The origin of the circular dichroism is shown to be a chiral configuration of the titanium orbitals in the skyrmions.

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Presenters

  • Margaret McCarter

    Department of Physics, University of California, Berkeley, University of California, Berkeley, Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.

Authors

  • Margaret McCarter

    Department of Physics, University of California, Berkeley, University of California, Berkeley, Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.

  • Sujit Das

    Department of Materials Science and Engineering, University of California at Berkeley, Department of Materials Science & Engineering, University of California, Berkeley, University of California, Berkeley, Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA., Physics Department, Univesity of California, Berkeley

  • Yun-Long Tang

    Materials Science Division, Lawrence Berkeley National Laboratory, University of California, Berkeley

  • Christoph Klewe

    Advanced Light Source, Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory

  • Padraic Shafer

    Advanced Light Source, Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory, Advanced Light Source

  • Elke Arenholz

    Advanced Light Source, Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory, Advanced Light Source

  • Javier Junquera

    University of Cantabria, Departmento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Departamento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Cantabria Campus Internacional, Avenidad de los Castros s/n, E-39005 Santan, Universidad de Cantabria, Cantabria Campus Internacional, Avenidad de los Castros s/n, E-39005 Santander, Spain.

  • Lane Martin

    Department of Materials Science & Engineering, University of California, Berkeley, University of California, Berkeley, Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA., Materials Science and Engineering, University of California, Berkeley, University of Illinois at Urbana-Champaign

  • Ramamoorthy Ramesh

    Department of Materials Science & Engineering, University of California, Berkeley, University of California, Berkeley